1. Field of the Invention
The present invention relates to an apparatus and method for communicating between two communication terminals and is particularly concerned with an apparatus and method for routing communication between the two terminals along a preferential route.
2. Discussion of the Background
In recent years many countries have liberalised their telecommunications systems. As a result, when a user operates a telephone, the user increasingly has a choice as to the network(s) used to carry his message. Each network has typically a different set of characteristics such as geographical extent, speed of transmission, and an associated cost.
Devices are known which automatically route messages along the route of least cost. As the route costings of the networks change, the routing information stored in these devices need to be updated as the least cost route may have changed. This updating is done by sending updated information along the telephone lines to the least cost route device.
A problem with known devices for least cost routing is that each device must be individually updated and hence a large amount of information is transmitted along the telephone lines.
It is known from U.S. Pat. No. 5,606,602 to broadcast by a radio signal bid information relating to a number of competing carriers to user terminals in a telephone system. Such terminals are provided with a processor enabling a decision to be made as to the least cost route based on the costing information received.
A disadvantage of such a system is that it requires intelligent processing at the terminal and also that commercially sensitive cost data may be broadcast.
According to the present invention there is disclosed an apparatus for routing telephone calls comprising; input means operable to receive an input signal representative of a user generated call number defining a user selected call destination; signal generating means operable to prefix the input signal with a prefix signal representative of a selected prefix code defining at least a network connection route selected from a plurality of available routes to the user selected call destination; memory means operable to store a decision table containing predetermined data for determining prefix codes corresponding to a plurality of respective call destinations; selecting means operable to obtain said selected prefix code corresponding to said user selected call destination by addressing the memory means; output means operable to output an output signal corresponding to the input signal prefixed by the prefix signal; receiving means operable to receive a wireless broadcast signal of updating information, and updating means operable to update the predetermined data stored in the decision table in accordance with the received updating information.
In embodiments of the present invention a large number of routing devices incorporating such apparatus may be updated simultaneously as, since the same information is required by many devices, all the devices within range of the transmitter of the information carried by free-space electromagnetic waves may pick up the broadcast information.
In accordance with a further aspect of the present invention there is provided a control centre for collating updating information and sending it to a transmitter to be broadcast to a number of routing devices. The control centre may send different updating information to the radio transmitters covering different geographical areas as the preferential route may change between the areas served by different transmitters.
Preferably the updating information is transmitted by a network of radio transmitters currently used for transmitting information to pagers. The updating information may be transmitted at a time when it is cheap to use the network of transmitters for transmitting information to pagers.
In accordance with a further aspect of the present invention, there is provided a telecommunications apparatus such as a telephone, facsimile machine or mobile cellular phone incorporating the above disclosed apparatus.
According to a further aspect of the present invention there is disclosed a method of operating a radio paging system comprising: transmitting radio paging signals by operation of a transmitter to radio pager devices in accordance with user demands for pager messages; identifying an off peak period in which spare capacity exists in the transmitter operation due to fluctuation in user demand; and transmitting telephone call routing information during an off peak period by operation of the transmitter to telephone call routing devices adapted to receive, store and subsequentially use the call routing information.
According to a further aspect of the present invention there is disclosed a method of collecting charging information for calls made via a plurality of telephone network service providers, comprising prefixing each call with a code representative of call management information identifying a charging control centre and a customer identifier; each network service provider collating call charging information for calls connected via their respective network and including the call management information; the service providers transmitting collated call charging information to the charging control centre; and wherein the charging control centre collates said call charging information for subsequent billing of customers corresponding to the customer identifiers.